ClassMetaClassWriter 需要恢复支持指定 ClassLoader #37
Description
java.lang.TypeNotPresentException: Type com/test/vbs/Facade not present
at com.alibaba.deps.org.objectweb.asm.ClassWriter.getCommonSuperClass(ClassWriter.java:1051)
at com.alibaba.bytekit.asm.ClassMetaClassWriter.getCommonSuperClass(ClassMetaClassWriter.java:43)
at com.alibaba.deps.org.objectweb.asm.SymbolTable.addMergedType(SymbolTable.java:1202)
at com.alibaba.deps.org.objectweb.asm.Frame.merge(Frame.java:1300)
at com.alibaba.deps.org.objectweb.asm.Frame.merge(Frame.java:1198)
at com.alibaba.deps.org.objectweb.asm.MethodWriter.computeAllFrames(MethodWriter.java:1611)
at com.alibaba.deps.org.objectweb.asm.MethodWriter.visitMaxs(MethodWriter.java:1547)
at com.alibaba.deps.org.objectweb.asm.tree.MethodNode.accept(MethodNode.java:767)
at com.alibaba.deps.org.objectweb.asm.tree.MethodNode.accept(MethodNode.java:647)
at com.alibaba.deps.org.objectweb.asm.tree.ClassNode.accept(ClassNode.java:468)
at com.alibaba.bytekit.utils.AsmUtils.toBytes(AsmUtils.java:80)
at com.taobao.arthas.core.advisor.Enhancer.transform(Enhancer.java:256)
at com.taobao.arthas.core.advisor.TransformerManager$1.transform(TransformerManager.java:59)
at java.instrument/java.lang.instrument.ClassFileTransformer.transform(ClassFileTransformer.java:246)
at java.instrument/sun.instrument.TransformerManager.transform(TransformerManager.java:188)
at java.instrument/sun.instrument.InstrumentationImpl.transform(InstrumentationImpl.java:563)
at java.instrument/sun.instrument.InstrumentationImpl.retransformClasses0(Native Method)
at java.instrument/sun.instrument.InstrumentationImpl.retransformClasses(InstrumentationImpl.java:167)
at com.taobao.arthas.core.advisor.Enhancer.enhance(Enhancer.java:446)
at com.taobao.arthas.core.command.monitor200.EnhancerCommand.enhance(EnhancerCommand.java:173)
at com.taobao.arthas.core.command.monitor200.EnhancerCommand.process(EnhancerCommand.java:120)
at com.taobao.arthas.core.shell.command.impl.AnnotatedCommandImpl.process(AnnotatedCommandImpl.java:82)
at com.taobao.arthas.core.shell.command.impl.AnnotatedCommandImpl.access$100(AnnotatedCommandImpl.java:18)
at com.taobao.arthas.core.shell.command.impl.AnnotatedCommandImpl$ProcessHandler.handle(AnnotatedCommandImpl.java:111)
at com.taobao.arthas.core.shell.command.impl.AnnotatedCommandImpl$ProcessHandler.handle(AnnotatedCommandImpl.java:108)
at com.taobao.arthas.core.shell.system.impl.ProcessImpl$CommandProcessTask.run(ProcessImpl.java:385)
at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at java.base/java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:304)
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
at java.base/java.lang.Thread.run(Thread.java:991)
Caused by: java.lang.ClassNotFoundException: com.test.vbs.Facade
at java.base/java.net.URLClassLoader.findClassInternal(URLClassLoader.java:497)
at java.base/java.net.URLClassLoader.findClass(URLClassLoader.java:456)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:626)
at com.taobao.arthas.agent.ArthasClassloader.loadClass(ArthasClassloader.java:34)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:558)
at java.base/java.lang.Class.forName0(Native Method)
at java.base/java.lang.Class.forName(Class.java:398)
at com.alibaba.deps.org.objectweb.asm.ClassWriter.getCommonSuperClass(ClassWriter.java:1049)
... 31 common frames omitted
也就是下面的代码里，都有可能获取到空的 type2Bytes， 这样子会调用 super.getCommonSuperClass，但默认情况下， classLoader是 ClassWriter 的 classLoader。
@Override
protected String getCommonSuperClass(String type1, String type2) {
byte[] type1Bytes = ClassLoaderUtils.readBytecodeByName(classLoader, type1);
if (type1Bytes == null) {
return super.getCommonSuperClass(type1, type2);
}
byte[] type2Bytes = ClassLoaderUtils.readBytecodeByName(classLoader, type2);
if (type2Bytes == null) {
return super.getCommonSuperClass(type1, type2);
}